Chromosome studies of trematodesOpisthioglyphe ranae(Plagiorchiidae) from different populations

Summary The diploid set of O. ranae from two localities, small rivers Penaquilla (Alicante province) and Gaibiel (Castellon province) in Spain, contain 22 chromosomes. The structure of karyotype was: 1st M+2nd T+3rd, 7–10 th SM+4th-6th ST+11th M-SM. Chromosomes of the first pair constitute 19.75% of the total haploid set length. A comparative karyological analysis of geographically separate O. ranae populations (from Spain, Poland and Crimea) showed the great karyological stability. Insignificant interpopulational differences in the morphology of 1st, 4th, 5th, 7th and 10th chromosome pairs were detected, which occurred as a result of small pericentric inversions.